Sixteen Amish men and women in Ohio face lengthy prison terms after being convicted of hate crimes including forcibly cutting off fellow sect members' beards and hair.

The defendants, with about 50 children between them and including six couples, were convicted on Thursday after four days of deliberations.

The defendants had rejected plea deals, and some could now get sentences of 20 years or more. Sentencing was scheduled for January. Members of the defence team said appeals were likely.

All the defendants are members of a settlement in eastern Ohio. Rhonda Kotnik, representing one of the defendants, Kathryn Miller, said the verdicts would destroy the community of about 25 families. "The community is going to be ripped apart. I don't know what's going to happen to all their children," she said.

Samuel Mullet Sr, 66, the leader of the breakaway group, was found guilty of orchestrating the attacks. The government said the cuttings were an attempt to shame members of the community who he believed were straying from their beliefs.

His followers were found guilty of carrying out the attacks. Prosecutors and witnesses described how sons pulled their father out of bed and chopped off his beard in the moonlight and how women surrounded their mother-in-law and cut off two feet of her hair, taking it down to the scalp in some places. The court heard that they targeted hair because it carried spiritual significance in the Amish faith.

Federal officials said the verdicts would send a message about religious intolerance. "The victims in this case are members of a peaceful and traditional religion who simply wanted to be left to practice their religion in peace," the US attorney Steven Dettelbach said. "Unfortunately, the defendants denied them this basic right and they did so in the most violent way."

Defence lawyers said their clients were bewildered by the verdicts. "They really don't understand the court system the way the rest of us have, being educated and reading newspapers," said Joseph Dubyak, who represented Linda Schrock.

The defendants argued that the Amish were bound by different rules guided by their religion and that the government had no place getting involved in what amounted to a family or church dispute.

Prosecutors said Mullet thought he was above the law and free to discipline those who went against him based on his religious beliefs. Before his arrest last November, Mullet said: "You have your laws on the road and the town – if somebody doesn't obey them, you punish them. But I'm not allowed to punish the church people?"

The hair cuttings, he said, were a response to continuous criticism he had received from other Amish religious leaders about him being too strict, including shunning people in his own group.

Witnesses testified that Mullet had complete control over the settlement that he founded two decades ago and described how his religious teachings and methods of punishments deviated from Amish traditions. One woman testified that Mullet coerced women at his settlement into having sex with him, and others said he encouraged men to sleep in chicken coops as punishment.